Apparatus for resilient cavity inspection or examination have been well-documented in the prior art, especially in the area of human medical apparatus for examination of body cavities. Looking in particular at surgical retractors that can also be termed speculum apparatus that are employed for the use of gynecological examinations the following general analysis of the speculum arts is given. Speculum's generally have blades shaped as extension fingers that are movable between a closed state and an open state, wherein the blades are typically formed as an elongated spoon shaped extension finger with one finger typically nesting within another finger in the closed state for a more streamlined penetration for insertion into the body cavity. Once the speculum is inserted into the body cavity, the speculum is then manually moved from the closed state to the open state, resulting in the subsequent spreading of some or all of the fingers to physically expand the body cavity for examination. As is the typical case for the majority of prior art speculums, the speculum fingers are pivotally connected at one end and are free on the other hand in a cantilevered type configuration.
The primary objective in the speculum's use is to allow the service provider examining the patient's body cavity or as typically the case a vagina, for the service provider to have a full and clear of view as possible of the area disposed within the cavity while also having as free and open access as possible around and through the speculum itself with the speculum acting to obfuscate or block the service provider's view or access in a minimal manner. In focusing upon the speculums pivotally connected fingers there exists an undesirable limitation in the service provider's viewing field of the body cavity and that the pivotal connection is fixed in its physical size adjacent to the pivotal axis of movement and does not allow for an increased field of vision as the fingers are manually expanded outward, i.e. in going from the closed state to the open state. In fact there could be some additional restriction of the service provider's view and access to the body cavity when the speculum fingers are moved from the closed state to the open state due to the fingers possibly pivoting inward on their end opposite of their cantilever end.
Focusing in particular on the vagina speculum which in the past has been primarily used to visualize the cervix and vagina walls in addition to gaining access to the uterus. As previously mentioned there is non-optimal limitation on a portion of the prior art speculums as to the pivotal connection of the fingers restricting the service provider's view and access to the interior of the vagina and in particular the vaginal wall structure. The vaginal wall structure poses a particular problem for service provider examination in that the vaginal wall structure is comprised of soft, somewhat unsupported, and fatty tissue that is difficult to control in the speculum structurally supporting the vaginal wall apart from itself somewhat resembling soft bread dough. This results in the speculum fingers opening up against the vagina walls in going from the closed state to the open state wherein the vaginal wall tissue surrounding the finger tends to collapse around the finger due to its lack of support stiffness resulting in a further hampering of the service provider's view of the inside wall vagina. This problem of the vaginal wall collapsing around the finger is especially prevalent if the patient is overweight, is older in age, or has had children through the vaginal tract.
Furthermore, as the vagina wall collapses around the finger, the reaction may be that the examining service provider is motivated to open the fingers to an even greater distance apart to gain a better visual of the cervix. However, this may be a self defeating effort as the previously mentioned problem of the vagina wall collapsing around the finger becomes even more acute as the figures are moved a further distance part, thus there is very little to be gained upon moving the speculum fingers further part to gain a better visual orientation of the vagina and cervix. Further, another problem of course is patient comfort, as the fingers are expanded further and further apart patient discomfort increases due to a number of issues such as the physical outward force as against the stretching of the introitus, in addition to the sliding and scraping action of the finger against the vagina wall also causing patient discomfort, and the subsequent risk of vagina wall pinching when the fingers are retracted into their closed state or nested position in preparation for extraction or withdrawing of the speculum from the vagina.
A number of prior art solutions have been proposed dealing with the different methods of which vagina walls are expanded for visual contact and physical access by the service provider while at the same time allowing for a minimal amount of blockage for the service provider to potentially use instruments in the vagina while at the same time being able to visualize the nature of the examination or therapeutic procedure that the service provider is performing. The majority of the early use speculums had pivotally connected fingers, typically having just two fingers that simply spread apart from the depression of a thumb lever which usually included a mechanism to lock the fingers in a particular pivotal position state in a selectable manner by the service provider. Although simple in design and easy to use, being somewhat similar to spreader pliers tools, the early use speculum having only two fingers and a pivotal connection at one end had limited ability to enhance visual contact of the service provider with the vagina walls due to the vagina with wall collapse as a position intermediate to the spread apart portions of the fingers, i.e. in the open state as previously described.
In addition, in the early use speculums due to the nature of the larger circumferential distance of each finger resulting in a larger area of the finger itself undesirably covered up larger portions of the vagina wall thus impeding visual and physical access of the service provider to the vagina wall. Plus, the early use speculum undesirably inflicting additional discomfort upon the patient as previously described due to the large amount of separating movement of the fingers to each other in going from the closed state to the open state. More refined solutions included speculum apparatus that used more than two fingers that could be opened in an iris aperture type of movement, wherein the fingers are moved outwardly in typically a spiraling motion. However, the iris type of speculum had two major drawbacks; the first drawback being that when each individual finger opened it moved through a circumferential type of arc and caused a relative sliding motion as against the vagina wall causing patient discomfort through a pinching of the vaginal wall tissue with the second drawback of the complex mechanism with which to move the fingers. Thus this circumferential arc finger movement of the iris type speculum can be compared to the pivotal speculum finger arrangement wherein the pivotal finger moves outwardly without circumferential arc movement, thus resulting in less discomfort for the patient.
The complex mechanism for the iris type of speculum further causes problems from potentially interfering with the service providers view and access to the vagina as a speculum should accommodate an open field of view and physical access along a longitudinal axis parallel to the fingers in the service provider being positioned at the non-inserting end of the speculum. Continuing, in looking to the pivotal type of speculums that use more than two fingers, wherein the undesirable circumferential arc movement is eliminated, again the problem of having three or more fingers having to have a complex mechanism usually located at the position where the service provider needs the maximum access and field of view for the vagina is a drawback.
Although the multitude of speculum fingers being more than two fingers pivoting outward without circumferential arc movement for less patient discomfort as previously described, does positively provide for less distance between each finger in the open state resulting in a reduced span of distance for the vaginal wall to droop between fingers thus giving the service provider greater access and visualization of the vagina, in addition to the reduction in patient discomfort as the fingers do not need to be as far apart from one another as compared to the two finger speculum. However, having more than two fingers adds complexity to the mechanism for moving the fingers in-between the closed state and the open state which adds size and weight to the speculum on the end opposing the cantilevered finger portions. Thus a speculum having more than two fingers in generally beneficial by helping reduce the occurrence of the vagina wall collapsing from around the finger and the resulting loss of view and access for the service provider and for reducing patient discomfort. Further, it should be noted that as these speculum apparatus are a manually hand held instrument; size and weight are considerations that should be desirably minimized.
Continuing, in looking at some specific examples in the prior art starting with the typical early use type speculum, in U.S. Pat. No. 5,997,474 to Batchelor disclosed is a vaginal speculum comprising two arms hinged with one another at a point along their length and forming a pair of jaws on one side of the hinge point and a pair of handles on the opposite side of the hinge point such that the jaws can be separated by squeezing together the handles. An elongated locking member in Batchelor is pivotally mounted to one handle, with the locking member having enough friction to hold it in position against its weight, reference column 1, lines 29-33 and lines 43-46. Batchelor had added the features of an elongated handle for the entire hand of the service provider to be able to grip the speculum as opposed to the thumb lever that had been previously employed on earlier speculums to give more opening force to the arms and including a new design locking member to hold the arms in a selected position apart.
Similar to Batchelor in design for the spreading apart fingers and the pivotal handle arrangement, in looking at U.S. Pat. No. 6,416,466 to Hsiao disclosed is a vaginal speculum that is made of metal or plastic including an upper and a lower jaw forming a concave profile. In Hsiao, the end part of the jaw opposite from the insertion end of the lower jaw is extended, whereby a patient's secretion can be exhausted or channeled along the extended end part for avoiding contact with the service provider's hands, reference column 1, lines 43-48 and lines 56-60. In addition to the new secretion irrigation channel, Hsiao has a plurality of buckling members used for locking the jaws into a selected position. In addition, in being somewhat similar to Batchelor and Hsiao, in having a veterinary application speculum, in Ukraine patent number UA 9,393 U to Tsymerman et al. disclosed is a vaginal speculum for examining females of large animals equipped with reflector and electric lamp connected with a power supply. In Tsymerman et al., the movable handle of the upper branch is attached with the fixed handle of the lower branch by the retainer screw with two nuts for the locking mechanism of the spreadable fingers including the addition of a light adjacent to the upper finger.
Continuing further, in an example of an iris type of expanding speculum, in U.S. Pat. No. 6,354,995 to Hoftman et al. disclosed is a rotational lateral expander apparatus having multiple blades. As a typical example, four blades in Hoftman et al., are arranged so that their forcing planes are facially parallel to each other in a closed or nested position, reference column 1, lines 51-57. In Hoftman et al., specifically referring to FIGS. 1 to 5, it can be seen that the blades must have a sliding motion as against the vaginal wall structure which can lead to patient discomfort as the vaginal wall structure can be pulled, compressed, and pinched as the blades move from their closed state to their open state and in returning from the open state to the closed state. Hoftman et al., has the feature of the translation of forceps type movement into the iris type movement through a mechanism to effectuate the blades going from the closed state to the open state in the rotating base plate that connects to a lateral expansion of the blades that open laterally and rotationally simultaneously.
As an example of a pivotal blade speculum having more than two blades in looking at U.S. Pat. No. 6,280,379 to Resnick disclosed is a speculum using small “bullet shaped” diameter tips on the distal ends of the blades which may be comprised of plastic, or coated metal to reduce friction, or reduce the “cold” sensation of the patient, reference column 2, lines 55-67. The Resnick speculum also has four blades to expand the vaginal walls, with three of the blades actually having expanding/contracting movement in somewhat of a mechanically open manner, having a degree of free play as between the blades and the handle structure. Due to the larger and somewhat complex mechanism in Resnick required to expand and retract three blades from a pistol grip handle, say as compared to the simple and small mechanism in Batchelor for example, the Resnick speculum is slightly heavy and cumbersome, being an undesirable feature of a manually hand held instrument. Further to this in Resnick, the additional hand squeezing force required to move three blades as compared to the prior art moving a single blade, again as in Batchelor, adds to the difficulty in using the Resnick speculum. In Resnick this would be considered a design requirement as a greater mechanical advantage mechanism, as between the compressible handgrip and blades, has been employed to a limited extent with the blade hook end 16, see FIG. 1 (closed state) and FIG. 5 (open state), i.e. the travelling ring 10 moving further from the blade pivot point sleeve 18 that is upon the stationary ring 8, resulting in a greater moment arm, which is a positive. However, Resnick does not really take full advantage of this moment arm increase due to only a portion of the travelling ring 10 force taking advantage to the increased moment arm as the distance between the travelling ring 10 and the blade pivot point sleeve 18 upon the stationary ring 8 remains substantially constant in an axis perpendicular to the force vector on the travelling ring 10 when moving the blades from the closed state to the open state.
A further example of a four blade speculum that addresses the mechanical complexity issue for the three to four blade movement from the handgrip, is in U.S. Pat. No. 7,060,029 B1 to Hajianpour, that discloses a basically conventional early use type pivotal two blade speculum, i.e. designed for contacting the anterior and posterior vaginal wall portions being similar to Batchelor, with having the addition of attachable/removable opposing lateral blades, wherein the lateral blades are attached and removed when the conventional portion of the speculum is in an open state by compressing as against the anterior and posterior vaginal walls. Thus Hajianpour attempts to have the advantage of the four blade speculum without the complexity, size, and weight of three or four blades moving together from a handle grip, however, the compromise being disadvantage of the loose lateral blade pieces that have to be manually positioned and attached and removed each time an examination is performed. Close to Hajianpour in U.S. Pat. No. 6,146,467 B1 to McMillian et al., is another speculum with a conventional pivotally connected two finger design that “adds in” two additional lateral blades that have their own independent thumb screw adjustment that is not connected to the primary anterior and posterior fingers.
Another example of a four blade speculum is in United States patent number U.S. Pat. No. 6,869,398 B2 to Obenchain et al., that discloses the use of an extensive mechanism for the selectable positioning of the four blades, even though Obenchain et al., has a very elaborate blade positioning arrangement, the size and weight dictate that additional support is required as the speculum cannot be supported by the body cavity or the examining service provider's hand as evidenced by the desired stabilizing arm 40 in FIG. 1. A further example in the four dilator finger area is disclosed in U.S. Pat. No. 6,436,033 B2 to Tan that is somewhat similar to Resnick except that the pivotal actuator is disposed between the finger pivot point and the free cantilever end of the finger that is inserted into the vagina, however, only being for the third and fourth blades, reference fingers 14a and 14b. In Tan, the speculum basically starts with a conventional pivotal two blade arrangement like Batchelor and then adds the third and fourth fingers that have a subsequent pivotal contact after the anterior and posterior fingers have started to open. A drawback of Tan is that there is no real mechanical advantage in the design opening mechanism that could accommodate the additional opening force required when the examining service provider in squeezing the handle encounters the opening force of four fingers from two fingers.
An even further example in the four blade speculum area, in U.S. Pat. No. 5,377,667 and its continuation follow-on application in U.S. Pat. No. 5,505,690 both to Patton et al., disclosed is a speculum that utilizes a slider plate that acts as collet in moving parallel to the speculum finger longitudinal axis, wherein the slider plate is operable to open and close the fingers by movement along the finger longitudinal axis. In Patton et al., although the slider does accomplish its purpose in opening and closing the fingers desirably, however, the slider plate adds considerable bulk and weight to the speculum opposite of the finger cantilever ends being undesirable from a service provider's standpoint plus the attendant problem of obscuring the service provider's vision and instrument access through the speculum center that is adjacent to the finger pivotal end portions opposite of the finger cantilever ends, see in particular FIGS. 6, 7, and 8.
What is needed is an examination apparatus or more particularly a speculum that does preferably utilize more than two fingers to reduce, in the finger open state, the finger to finger span distance that allows the lax vaginal wall tissue to prolapse while the speculum is inserted into the introitus of the vagina and subsequently moved to the open state of the fingers. Also, the desirable speculum would at the same time provide the examining service provider the maximum field of view through the proximal portion of the speculum being the non-insertion end of the apparatus, plus the included feature that also equates to allowing for other instruments to be used in this field of view access area. Further, the desired speculum would have a mechanism to accommodate the kinematics from the actuation structure or handle to the finger movement that would employ a greater mechanical advantage than what has been taught by the prior art for enhancing the operating experience of the examining service provider in requiring less hand grip strength as a greater number of fingers, being more than two fingers that ends up resulting in less hand fatigue for the service provider for multiple examinations that are performed in the course of the day. In addition, the entire apparatus would be of a minimal size and weight which is always a welcome feature in a hand held manually actuated speculum apparatus. Continuing, the speculum would be operable to help minimize patient discomfort by the finger having little sliding type movement as against the vaginal wall structure and having to open the fingers a minimal amount for the examining service provider to have sufficient visual and instrument access, while minimizing vaginal wall structure prolapse between the fingers in their open state, that results in maximizing the visual and instrument access to the vagina from the examining service provider through the speculum.
The vaginal wall prolapse issue is primarily due to lax vaginal wall tissue tone which is fairly common and is most typically associated with a woman having natural childbirth through the vaginal tract, or elderly women, or obese woman. Thus currently, with use of the prior art two blade or two finger speculum due to the aforementioned lax vaginal tone, the service provider typically has to open the fingers further apart to have an adequate view, with this further opening or spreading of the speculum fingers causing the patient a higher level of discomfort due to speculum finger pressure as against the bladder and/or urethra. Thus, the desirability of having more than two speculum fingers in a minimally sized and weighted speculum that could facilitate easy one-handed operation by the service provider would be substantially optimal by allowing the service provider to use their other hand for viewing lights, instruments, and the like. Further, the desirable speculum would have as previously mentioned the degree of mechanical advantage in the hand grip to blade movement mechanism that facilitates the opening of greater than two fingers without the need for excessive grip compression strength on the part of the using service provider. Other desirable features of the speculum would include; non-vaginal wall tissue pinching fingers, minimal-heat transfer fingers-to reduce the “cold” sensation for the patient, or minimal electrical conductance fingers for performing electro-surgical procedures, and further a possible light source for viewing the vaginal cavity with the speculum inserted into the vagina and in the open state, in addition to a fluid communication medium to facilitate adding or removing fluids from the vagina.